Cameron warns ministers not to step out of line over Brexit

British Prime Minister David Cameron warned Euroskeptic cabinet members Monday not to speak out of turn in the run-up to the British referendum on EU membership. He also told ministers to treat each other “with appropriate respect and courtesy” during the campaign.

Despite promising MPs a free vote in the referendum, to be held before the end of 2017, Cameron wrote to ministers telling them not to make the case for Brexit in parliament, and not to speak out on the issue before he secures an agreement on reform with fellow EU leaders.

Cameron will discuss the U.K.’s future in Europe at a summit in Brussels in February. On Sunday, he said that if a deal is struck next month, the referendum would be held this summer.

In Monday’s letter, Cameron said that once the referendum date has been set, only ministers who have “long-standing and sincerely held views” will be allowed to oppose the government line.

Until the date is fixed, “all ministers should continue to support the position set out in our manifesto and say or do nothing that will undermine the government’s negotiating position.”

He also said that civil servants will not be able to “support ministers who oppose the government’s official position by providing briefings or speech material on this matter.”

Until the final 28 days of the campaign, ministers’ special advisers will be able to help Euroskeptics, as long as they do so “in their own time.” During the last 28 days, so-called purdah rules will apply, limiting government announcements and spending.

The prime minister said the government had to remain “a united, harmonious, mutually respectful team.”